Apparatus for concentrating a blanket of dry steam for an extended area on a pulp mat



EAM

March 29, 1966 J. H. DUPASQUIER APPARATUS FOR OONGENTRATING A BLANKET OFDRY ST FOR AN EXTENDED AREA ON A PULP MAT 2 sheetssheet 1 Filed Dec. '7,1964 INVENTOR. JOSEPH H. DUPASQUIER ATTORNEY March 29, 1966 j QUER3,242,587

APPARATUS FOR CONCENTRATING A BLANKET 0F DRY STEAM FOR AN EXTENDED AREAON A PULP MAT Filed Dec. '7, 1964 2 Sheets-Sheet 2 F 4JOSEPHINF-Y%D'EESQUIER ATTORNEY the mat and steam are pulled between therolls.

United States Patent Office 3,242,587 Patented Mar. 29, 1966 3,242,587APPARATUS FOR CON CENTRATING A BLANKET F DRY STEAM FOR AN EXTENDED AREAON A PULP MAT Joseph H. Dupasquier, 560 E. Clarendon St.,

. Gladstone, Oreg.

Filed Dec. 7, 1964, Ser. No. 416,289 4 Claims. (Cl. 3460) This inventionrelates in general to the subjecting of the pulp mat, in the process ofmanufacturing paper and the like, to the application of heat through themedium of dry steam for the purpose of facilitating the drainage ofwater from the pulp mat and also for the purpose of raising thetemperature of the mat preparatory to its passage through presses anddrier rolls.

It is well-known that the heating of the pulp mat in- Creases the rateat which and the extent to which the mat will lose moisture in itstravel through the press sections of the paper machine. It is also knownthat the special application of heat to the mat immediately prior to itspassage into the drier section of the machine reduces the likelihood ofthe mat becoming so sticky as to have tendency to stick to the heateddrums as a result of the abrupt considerable change in temperatureproduced by contact with the drums. Dry heated steam, applied to thepulp Web, is a most satisfactory means for securing such desired heatingof the mat for these purposes.

traveling pulp mat at the point where the mat passes between two rolls,that is to say, if the steam moves along on the mat to the ingoing nipbetween the rolls, the rolls act to draw the steam on through the mat asThus there is a greater penetration of the steam into and through themat as a result of the passage of the steam with the mat through therolls. The increased penetration of the dry steam into the mat increasesthe heating imparted to the mat by the steam and consequentlyfacilitates the desired drainage of water from the mat.

-Where one of the rolls of the pair, forming the nip into which thesteam is drawn with the mat, is a suction roll, such as a suction couchroll, the effectiveness of the steam penetration is even morepronounced.

Means have heretofore been developed for applying dry steam to a pulpmat in advance of the passage of the mat into the nip between a pair ofrolls, but with such means it has not been possible to maintain thesteam in contact with the mat until the mat actually reaches the nipbetween the rolls, with the result that the increased effectiveness ofhaving the steam carried along with the mat through the nip is notobtained. On the other hand, the additional spraying of steam onto themat at the nip has not been found to be either effective or a practicaland at best it involves a considerable waste of steam.

Accordingly a special related object of the present invention is toprovide an apparatus for applying dry steam to a pulp mat which will notonly cause a blanket of steam to be maintained in contact with the matover a considerable area but will also make it possible for such steamblanketed area to be extended actually up to the nip between a pair ofrolls through which the mat passes.

Anadditional object is to provide an apparatus for applying suchextended steam blanket no the pulp mat or web which will be readily andsufficiently adjustable to meet operating conditions and will notpresent any particular operation or maintenance problem.

The manner in which these objects are attained and the construction andmanner of function of the device of the present invention will bereadily understood from the following brief description. In thedescription reference is made to the accompanying drawings wherein:

FIG. 1 is a fragmentary side elevation of the apparatus showing the samein full lines in operating position and in broken lines in withdrawninoperative position;

FIG. 2 is a fragmentary plan view, taken on the line indicated at 22 inFIG. 1, but drawn to a larger scale, with some portions omitted and someportions broken away and shown in section for clarity;

FIG. 3 is a foreshortened sectional elevation taken on line 33 of FIG. 2drawn to a still larger scale;

FIG. 4 is a fragmentary section taken on the line indicated at 44 inFIG. 2 drawn to the same scale as FIG. 3; and

FIG. 5 is a fragmentary sectional elevation on line 5-5 of FIG. 2.

Referring first to FIGS. 1 and 2, the apparatus includes an elongatedsteam chamber designated as a whole by the reference character 10, whichsteam chamber will be described in somewhat more detail later. Thissteam chamber has a length equal to, preferably not more than slightlygreater than, the width of the pulp mat 11 on which the steam is to beapplied. The housing of the steam chamber 10 includes a pair of verticalend walls 12 and 13. A pair of identical parallel horizontal angle ironsupporting arms 14 and 15 (FIG. 2) are rigidly mounted on each of thesewalls 12 and 13 by suitable welding and extended outwardly therefrom,being reinforced by bracing bars 14' and 15 respectively. Stub shafts 16and 17, secured on the arms 14 and 15 respectively extend out beyond theends of the arms and rotatably support grooved wheels 18 and 19respectively. The supporting assembly for the apparatus includes a pairof vertical side plates 20 and 21 each provided with a pair of curvedslots 22 and 23 shaped as shown in FIG. 1, which slots serve asguideways for the supporting wheels 18 and 19 respectively at each side.The side plates 20 and 21 in turn are removably and adjustably securedon a pair of suitable side members 24 and 24' respectively (FIGS. 1 and2) constituting part of the supporting assembly (not shown) for thepaper making machine, the side plates 20 and 21 each having a pluralityof outwardly extending lugs 52 and 53 with reduced threaded ends adaptedfor being clamped in slots in the members 24 and 24' of the machinesupporting assembly.

Each of the side plates 20 and 21 carries an upwardly extending bracket25 at the top end and each bracket supports a suitable stub shaft onwhich an ear 25, extending from the end of an air cylinder 27, ispivotally mounted. The two cylinders 27 are identical and aredouble-acting air cylinders and the piston in each cylinder carries apiston rod 28. The outer bottom end of each piston rod 28 is pivotallyattached to an anchoring plate 29 which in turn is welded to the arms 14and 15 and corresponding bracing bars 14' and 15' from the correspondingend of the housing for the steam chamber 10. Thus, as indicated in FIG.1, the simultaneous operation of the two cylinders 27, 27, enables thehousing for the steam chamber 10 to be moved as permitted by the shapeand extent of the pair of curved slots 22 and 23 in each of the verticalside plates 20 and 21, and thus enables the steam chamber housing to bemoved from the operative position, indicated by the full lines in FIG.1, to the withdrawn inoperative position indicated by the broken linesin that figure.

The housing for the steam chamber 10 includes, in addition to the twovertical end Walls 12 and 13, an

elongated shell forming the top and side walls, the upper portion ofwhich shell is substantially semi-cylindrical, and the sides of whichthence continue downwardly to the bottom of the housing in substantiallyparallel planes. The bottom or underside of the steam chamber housing(see FIG. 3) is formed into V-shaped ridges 30 and intervening V-shapedvalleys 31, extending from one end wall to the other. The two valleys 32along each side, formed by the junction of the bottom of the housingwith the side walls, are located below the level of the other valleys 31as shown in FIG. 3. Depending upon the size of the steam chamber 10,suitable reinforcements (not shown) are provided for the bottom wall inthe housing to insure rigidity for the housing bottom.

The steam chamber is similar to the device described in my United StatesPatent No. 2,838,982, issued under date of June 17, 1958, and entitled"Apparatus for Applying Dried Steam to a Pulp Mat to Evaporate WaterTherefrom, to which reference should be made.

Along each of the V-shaped ridges 30 of the bottom of the steam chamberhousing are a plurality of identical equally-spaced orifices 33 throughwhich steam jets are directed downwardly, as indicated in FIG. 3. Drainoutlets 34 are provided in each of the end walls 12 and 13 for the.valleys 31, and similar drain outlets 35 are provided for the lower sidevalleys 32. Suitable taps (two of which are shown at 36 in FIG. 4, butwhich are omitted from FIG. 2) at these outlets enable the watercollected in the valleys 31 and 32 to be drained oft. Since the orificesthrough which the steam jets are discharged from the steam chamber arerestricted to the ridges 30 the steam jets will be substantially freefrom drops of water or condensate particles which otherwise would bedischarged with the steam.

Steam is delivered into the steam chamber 10 through a pair of flexiblehoses 37 and 38 at the end walls 12 and 13 respectively. It will benoted from FIG. 2 that the discharging ends of these hoses on the endwalls 12 and 13 are not in alignment with each other but are locatednearer opposite sides. This is done so that the flow of steam into thesteam chamber from one end will not meet the flow into the chamber fromthe other end head on but will move along past the other flow and thusenable the pressurized distribution and circulation of steam to beequalized throughout the entire steam chamher.

A steam-confining shield, indicated as a whole by the referencecharacter 39, extends from the side of the bottom of the steam chamberhousing in the direction in which the mat 11 is traveling. In otherwords, the shield 39 extends from the steam chamber housing along abovethe mat in the, direction of travel of the mat, and extends towards aningoing nip between a pair of rolls, such as the nip between the rolls4%) and 41, shown in FIG. 1, through which the mat 11 passes. The shield39 comprises a top plate 42 having a plurality, of reinforcing strips 43(FIG. 2) on the top side, a pair of substantially vertical lateralflanges 44 and 45, and a terminal flange 46 (shown best in FIG. 3)sloping obliquely forwardlydownwardly.

The shield 39 is connected with the housing for the steam chamber 10 bysuitable hinge elements 4'7 attached to the reinforcing strips 43 on theshield and to reinforcing strips 48 extending part way around theoutside of the housing for the steam chamber 10. Suspension rods 49 forthe outer or terminal side of the shield 39 have their lower endsattached to cars 50 on the shield and their upper ends adjustably heldin bosses 51 secured to the reinforcing strips 48 on the steam chamberhousing.

The vertical lateral flanges 4'4 and 45 of the shield 39 extend belowthe top plate 42 of the shield, and may also extend above the top plate42 as shown for adding increased reinforcement. When the entireapparatus is in operating position as indicated in FIG. 1, the bottomedges of the lateral flanges 44 and 45 and the bottom edges of the endwalls 12 and 13 of the steam chamber housing preferably are made to liein the same plane, such plane being substantially parallel to thatportion of the pulp mat 11 subjected to the desired blanket of steam.Preferably the spacing of this plane of the bottom edges of the lateralflanges 44 and 45 and end walls 12 and 13 above the top face of the pulpmat should be from one-quarter of an inch to one-half of an inch, and insuch case the amount of steam lost by passing out over the side edges ofthe traveling mat will be relatively small. The adjustable mounting lugs52 and 53 (FIGS. 1 and 2) by which the side plates 20 and 21 aresupported on the main machine frame members 24 and 24', contribute inenabling the spacing of the housing forthe steam chamber 10, andtherewith the spacing of the shield 39, above the traveling mat to beadjusted as desired.

As previously mentioned, the terminal flange 46 of the shield 39 extendsobliquely with respect to the top plate 42 instead of beingperpendicular thereto. The angularity of this flange preferably, asillustrated in FIG. 3, is such that at no point along the outer face ofthe flange will the spacing between the flange and the adjacent surfaceof the upper roll of the pair of rolls forming the nip be excessive.While it would be possible to have this flange 46 curved to conform evenmore closely to the adjacent surface of the upper roll, the straightflange extending obliquely in the manner illustrated in FIG. 3 has beenfound to be amply satisfactory since the rapid travel of the surface ofthe upper roll and of the mat into the nip prevents any appreciableamount of steam from beneath the shield 39 passing upwardly between theflange 46 and the roll surface in the opposite direction. Alsopreferably the bottom edge of this terminal flange 46 extends in thesame plane with the bottom edges of-the lateral flanges 44 and 45, and,as previously mentioned, thus ordinarily in the same plane with thebottom edges of the end walls 12 and 13 of the steam chamber housing,although the position of the shield and its flanges with respect to thesteam chamber housing may be adjusted slightly by adjustment of thesuspension rods 49.

As apparent from FIG. 3, the space beneath the underside of the steamchamber housing forms an enclosed area on the traveling mat 11, intowhich area the dry steam under pressure is delivered from the orifices33 in the bottom of the steam chamber. As a result in this enclosedarea, designated as A in FIG. 3, a blanket of steam is maintained incontact with the mat and causes heating of the mat at that area andpenetration of some of the steam into the surface of the mat. However,the continued delivery of steam from the steam chamber into thisenclosed area A forces steam to escape from this enclosed area and themain avenue of escape of the excessive steam will be along the pathfollowed by the traveling web below the side of the steam chamberhousing and thus into the second enclosed area, designated as B in FIG.3, within the shield 39. The constant passage of steam into this secondenclosed area B results in the blanket of steam being maintained incontact with the mat throughout this added area.

The continued passage of the steam from enclosed area A into the secondenclosed area B forces excess steam from the second area B to find afurther subsequent major avenue of escape, and, again under theinfluence of the traveling web, this final discharge of steam from theapparatus occurs mainly under the terminal flange 46 of the shield 39.However, since the escaping steam from the second area B at this pointis in such close proximity to the nip between the rolls 40 and 41, thesteam is caused to be drawn along into the ingoing nip with the mat,with the result that the penetration of the steam into the mat andheating of the mat by the steam will be increased still more.

When the entire apparatus is to be employed in the optimum workingposition as indicated in FIG. 1', and

thus with the terminal edge of the shield 39 extending into closeproximity with the ingoing nip between the rolls 40 and 41, specialmeans is required for enabling the entire apparatus to be moved quicklyand easily away from the mat and rolls at the conclusion of the machineoperating cycle. The manner in which the housing for the steam chamberis supported through the medium of the slotted mounting plates 20 and 21enables the steam chamber housing, and with it the special shield 39, tobe moved into a withdrawn inoperative position quickly and easily by thedouble-acting cylinders 27, 27, as previously described,

I claim:

1. In an apparatus for concentrating an extended blanket of steam on apulp mat, a steam chamber housing located above the pulp mat and of theproper length to extend transversely across said mat, said housinghaving a main bottom wall and top, side and end walls, the bottoms ofsaid side and end walls terminating in a plane below said main bottomwall and forming an enclosed area beneath said housing, means fordelivering steam under pressure into said housing, said main bottom wallhaving steam jet orifices discharging downwardly from said main bottomwall, a shield extending from one side of said housing in the directionof travel of the mat and normally substantially parallel to said mat,said shield extending entirely across said mat, means connecting theadjoining edge of said shield with said housing, means supporting theopposite terminal edge of said shield from said housing, and means forpositioning said housing and therewith said shield in desired locationover said mat, whereby when a blanket of steam is maintained on said matbeneath said housing the steam blanket will be extended over the areabeneath said shield.

2. An apparatus for concentrating an extended blanket of steam on a pulpmat including a steam chamber housing located above the pulp mat and ofthe proper length to extend transversely across said mat, said housinghaving a main bottom wall and top, side and end walls, the bottoms ofsaid side and end walls terminating in a plane below said main bottomwall and forming an enclosed rectangular area beneath said housing,means for delivering steam under pressure into said housing comprising apair of steam delivery tubes connected to the ends of said housingrespectively in staggered relationship, said main bottom wall of saidhousing formed into ridges and valleys extending transversely acrossover said mat, said ridges having steam jet orifices dischargingdownwardly from said main bottom wall, a shield extending from one sideof said housing in the direction of travel of said mat and normallysubstantially parallel to said mat, said shield extending entirelyacross said mat, supporting elements on said housing for said shield,and means for adjustably positioning said housing and therewith saidshield in desired location over said mat, said last mentioned meansincluding a pair of vertical support plates mounted near opposite sidesof said mat respectively extending above said mat, a pair of wheelssupported on each end of said housing, each of said support plateshaving a pair of guideways for said wheels respectively, and means formoving said housing and wheels in said guideways.

3. An apparatus for concentrating an extended blanket of steam on a pulpmat, including a steam chamber housing located above the pulp mat and ofthe proper length to extend transversely across said mat, said housinghaving a main bottom wall and top, side and end walls terminating in aplane below said main bottom wall and forming an enclosed rectangulararea beneath said housing, means for delivering steam under pressureinto said housing, said main bottom wall of said housing having steamjet orifices discharging downwardly from said bottom wall into saidrectangular area, a shield extending from one side of said housing inthe direction of travel of said mat and extending entirely across saidmat, said shield having a top plate normally substantially parallel tosaid mat, a pair of lateral flanges on said top plate extending downnear the lateral edges of said mat respectively and together with saidtop plate forming a secondary enclosed area on said mat adjoining theenclosed area beneath said housing, a terminal flange on said top plateextending transversely over said mat and extending obliquely downwardlyand forwardly in the direction of travel of said mat, means connectingthe adjoining edge of said shield with said housing, suspension meanssupporting the opposite terminal edge of said shield from said housingand so arranged as to maintain said shield suspended along over said matwhen said housing and shield are in normal operating position, and meansfor poistioning said housing and therewith said shield in desiredlocation over said mat.

4. An apparatus for concentrating an extended blanket of steam on a pulpmat comprising a steam chamber housing located above the pulp mat and ofthe proper length to extend transversely across said mat, said housinghaving a main bottom wall and top, side and end walls, the bottom ofsaid housing and end walls terminating in a plane below said main bottomwall and forming an enclosed rectangularly-shaped area beneath saidhousing, means for delivering steam under pressure into each end of saidhousing comprising a pair of steam delivery tubes connected to the endsof said housing respectively in staggered relationship, said main bottomwall of said housing formed into ridges and valleys extending from oneend of said housing to the other, said ridges having steam jet orificesdischarging downwardly from said main bottom wall into said rectangulararea, a shield extending from one side of said housing in the directionof travel of said mat and extending entirely across said mat, saidshield having a top plate normally substantially parallel to said mat, apair of lateral flanges on said top plate extending down near thelateral edges of said mat respectively and together with said top plateforming a second enclosed rectangular area above said mat adjoining theenclosed area beneath said housing, a terminal flange on said top plateextending transversely over said mat and extending obliquely downwardlyand forwardly in the direction of travel of said mat, hinge meansconnecting the adjoining edge of said shield with said housing,adjustable suspension means supporting the opposite terminal edge ofsaid shield from said housing so arranged as to maintain said shieldsuspended over said mat substantially parallel to said mat when saidhousing and said shield are in normal operating position, and means foradjustably positioning said housing and therewith said shield in desiredlocation over said mat, said last mentioned means including a pair ofvertical sup port plates mounted near opposite sides of said matrespectively extending above said mat, a pair of wheels supported oneach end of said housing, each of said support plates having a pair ofguideways for said Wheels respectively, and means for moving saidhousing and wheels in said guideways, whereby said shield will cooperatewith said steam chamber housing in maintaining a blanket of steam on anextended area over said mat, and whereby, with the proper positioning ofthe apparatus, said shield can be caused to extend into close proximitywith the nip between a pair of rolls for said mat and cause steam beyondsaid extended blanket to be drawn into the nip with said mat.

References Cited by the Examiner UNITED STATES PATENTS 2,366,484 1/1945Bradner 341 14 X 2,804,693 9/1957 Brodie 34-122 2,861,354 11/1958Hultgreen 34-160 2,919,495 1/1960 Underbay 34-114 3,097,994 7/ 1963Dickens 34-160 3,176,411 4/1965 Jepson 34-160 WlLLIAM J. WYE, PrimaryExaminer.

1. IN AN APPARATUS FOR CONCENTRATING AN EXTENDED BLANKET OF STEAM ON APULP MAT, A STEAM CHAMBER HOUSING LOCATED ABOVE THE PULP MAT AND OF THEPROPER LENGTH TO EXTEND TRANSERSELY ACROSS SAID MAT, SAID HOUSING HAVINGA MAIN BOTTOM WALL AND TOP, SIDE AND END WALLS, THE BOTTOMS OF SAID SIDEAND END WALLS TERMINATING IN A PLANE BELOW SAID MAIN BOTTOM WALL ANDFORMING AN ENCLOSED AREA BENEATH SAID HOUSING, MEANS FOR DELIVERINGSTEAM UNDER PRESSURE INTO SAID HOUSING, SAID MAIN BOTTOM WALL HAVINGSTEAM JET ORIFICES DISCHARGING DOWNWARDLY FROM SAID MAIN BOTTOM WALL, ASHIELD EXTENDING FROM ONE SIDE OF SAID HOUSING IN THE DIRECTION OFTRAVEL OF THE MAT AN NORMALLY SUBSTANTIALLY PARALLEL TO SAID MAT, SAIDSHIELD EXTENDING ENTIRELY ACROSS SAID MAT, MEANS CONNECTING THEADJOINTING EDGE OF SAID SHIELD WITH SAID HOUSING, MEANS SUPPORTING THEOPPOSITE TERMINAL EDGE OF SAID SHIELD FROM SAID HOUSING, AND MEANS FORPOSITIONING SAID HOUSING AND THEREWITH SAID SHIELD IN DESIRED LOCATIONOVER SAID MAT, WHEREBY WHEN A BLANKET OF STEAM IS MAINTAINED ON SAID MATBENEATH SAID HOUSING THE STEAM BLANKET WILL BE EXTENDED OVER THE AREABENEATH SAID SHIELD.